Polyoxyalkylene polyamine vulcanizing agents for epichlorohydrin polymers

ABSTRACT

Polyoxypropylene polyamines are vulcanizing agents for halogencontaining polymers such as polyepichlorohydrin. The cured polymers are useful specialty rubbers which are resistant to ozone attack.

United States Patent George Phillip Speranza;

Harold George Waddill, both of Austin, Tex.

Jan. 2, 1969 Sept. 21,1971

Jefierson Chemical Company, Inc. Houston, Tex.

inventors Appl. No. Filed Patented Assignee POLYOXYALKYLENE POLYAMINE[56] References Cited UNITED STATES PATENTS 3,158,580 11/1964 Vandenberg260/2 3,236,895 2/1966 Lee et a1. 260/5 84 3,414,529 12/1968 Green eta1. 260/2 3,453,357 7/1969 Logan 264/236 3,350,352 10/1967 Smith etal... 260/47 3,399,174 8/1968 Bvemmer 260/47 Primary Examiner-William H.Short Assistant ExaminerE Nielsen Attorneys-Carl G. Ries, John R. Kirk,Jr. and H. G. Jackson ABSTRACT: Polyoxypropylene polyamines arevulcanizing agents for halogen-containing polymers such aspolyepichlorohydrin. The cured polymers are useful specialty rubberswhich are resistant to ozone attack.

POLYOKYAlKYLENE POLYAMINE VULCANEZKNG AGENTS F 931 EEECHLORQHYDWINPQLYMERS BACKGROUND OF THE 1N VENTIQN 1. Field of the Invention Theinvention pertains to vulcanizing agents for halogencontaining polymersand the resulting vulcanizates.

2. Description of the Prior Art Anderson E. Robinson s U.S. Pat.3,026,270 teaches the use of hydrazine, aromatic amines andalkylenediamines as crossiinlting agents for polymeric epoxides.

SUMMARY OF THE INVENTION The invention is a process for vulcanizinghalogen-containing polymers such as polyepichlorohydrin by the use of apolyoxyalkylene polyamine vulcanizing agent of the formula R[(OA) ,Nl-lwhere R is a hydrocarbon radical, A is an alkylene radical of from twoto four carbon atoms, x has an average value from 1 to 50, and y is aninteger from 2 to 4. The group A of the formula represents lowerallcylene radicals such as ethylene, propylene 1,2-butylene,2,3-butylene, trimethylene and tetramethylene. Such amines are availableas the products of direct amination of a polyoxyalkylene glycol or theymay be obtained by other means such as the reduction of apoly-(cyanoalkyl) ether. The polyoxyalkylene polyamines useful in theprocess of my invention are mentioned in U.S. Pat. 3,236,895 andcopending U.S. Pat. Application 602,167 tiled Dec. 16, 1966, nowabandoned. The polyoxyalkylene polyamines are obtained by amination ofthe corresponding polyoxyalkylene polyol of the formula wherein R is thenucleus of an oxyalkylation-susceptible aliphatic polyhydric alcoholcontaining 2-12 carbon atoms and 2-8 hydroxyl groups, Z is an alkylgroup containing l-l8 carbon atoms, X and Y are hydrogen or Z, n has anaverage value of -50 and m is an integer of 2-8 corresponding to thenumber of hydroxyl groups originally present in the polyhydric alcohol.It can be seen that in the above formula if R is a 1,2 1,2-propyleneradical, Y is hydrogen, X and Z are methyl, n is one or more and m istwo, the products are those of U.S. Pat. NO. 3,236,895. However, if n iszero, the product is the diamine prepared from tripropylene glycol andis thus a lower molecular weight diamine than those that can be obtainedby the processes ofUS. Pat. No. 3,236,895.

DESCRlPTiON OF THE PREFERRED EMBODIMENTS Chlorine-containing polymers,in particular, polyepichlorohydrin and copolymers and terpolymersthereof, are vulcanized by reaction with polyoxyalkylene polyamines,particularly polyoxypropylene polyamines of varying molecular weight.The liquid polyoxypropylene polyamine curing agents of my invention actas plasticizers to the polymers and the cured products of my inventionare soft and tough rubberlike materials. This internal plasticizationeffect of the polyoxypropylene polyamines on polymers is shown in thelow modulus and hardness figures illustrated in the data below. Thesecured polymer products are particularly useful for specialtyapplications where low ox gen permeability, solvent resistance and lowtemperature flexibility is required. Such applications are in gaskets,hoses, sealants, etc. The polyoxypropylene polyamines are particularlyuseful in the process of my invention because of their compatibilitywith the polyether polymers. In addition, the polyoxyalkylene polyamineshave very low toxicity compared to the known amine curing agents.

The data in the tables below, illustrate the curing characteristics ofthe polyoxyalkylene polyamines in an epichlorohydrin-eLhylene oxidecopolymer trademarked Hydrin 200 by B. F. Goodrich Company. The numbersfollowing the polyoxypropylene polyamines represent the molecular weightof the compounds. The polyoxyalltylene polyamine is admixed with thepolymer before heating the mixture to a vulcanizing temperature. Forexample, the polyoxyalkylene polyamine and polymer may be blended bymilling on a conventional rubber mill. Any amount of polyoxyalkylenepolyamine may be used in the process of my invention, however from 0.5to 50 parts per hundred (phr.) is the preferred concentration range.Vulcanizing temperatures for my invention range from room temperature toabout 350 0, however, -200 C., is a preferred vulcanizing temperaturerange.

Other additives, generally used in the vulcanization of rubber, forexample, fillers, antidegrandants, accelerators, etc, can be present inthe process of my invention.

The data in table 3 illustrate four polyoxypropylene polyaminevulcanizing agents of my invention compared to the standard curing agentZ-mercaptoimidazoline vulcanized at C. for 30 minutes. The polymercompositions for vulcanization contain the following: 7 1

Parts Hydrin 200 100 Zinc stearate (lubricant) I Red lead (accelerator)5 Nickel dibutyldithiocarbamate (antidegradant) 1 Carbon black 30Vulcanizing agent As indicated The tensile strength, modulus andultimate elongation reported in the tables were measured according tothe American Society for Testing Materials (ASTM) method D638-64t. TheShore A Hardness was measured according to ASTM method PJZQE TABLE 1 Thepolyoxypropylene polyamine 400 of Table l is a compound of the structurewhere x=4.6.

The polyoxypropylene polyamines of this invention have a low vaporpressure and inhalation of vapors therefrom at room temperature does notpresent a health hazard. The compounds are only slightly toxic oningestion by animals and moderately toxic to the skin.

Male albino rats were fed three of the polyoxypropylene polyaminesuseful in this invention and the toxicity data recorded showed thesematerials to be only slightly toxic by ingestion. The polyoxypropylenepolyamines were incorporated into the diet of the rats for 31 days. Thebehavior of the animals was unchanged and there were no deaths in a 31-day test period. No relevant gross pathology was noted after the animalswere killed at the end of the study.

Four of the polyoxypropylene polyamines useful in this invention wereplaced on the skin of albino rabbits and the toxicity data recordedshowed only moderate toxicity to the skin. However, diamines such as thealkylene diamines are highly toxic to the skin.

Having thus described our invention, we claim:

1. A method for vulcanizing homopolymers of epichlorohydrin andcopolymersof epichlorohydrin and e ne as d QtEhP PKh sL- i admixingthe-polymer with a curing agent Tithe formula K L HI where R is analiphatic hydrocarbon radical, A ie an alkylene ;radical of from two tofour carbon atoms, x has an average;

value from i to 50, and y in an integer from 2 to 4 and heating im r regesuriaat mua ug 2. A method for vulcanizing a chlorine-containingpolymer according to claim I wherein A of the formula la propylene. 3. Amethod for vulcanizing a polymer according to claim 2 wherein the curingagent it a polyoxypropylene polyamine. having a molecular weight fromabout 180 to about 3.000. 1 y 4. A method for vulcanizing a polymeraccording to claim 3 .wherein a in the polyoxypropylene polyamineformula has an average value of 6 and y la 2.

5. A method for vulcanizing a polymer according to claim 3: wherein a inthe polyoxypropylene polyamine formula has an !average value of 3 and yin 2.

6. A method for vulcanizing a polymer according to claim 3 i 9. Ahomopolymer of epichlorohydrin or copolymer of epichlorohydrln andethylene oxide vulcanized with a curing agent of the formula K MJ JYwhere R it an aliphatic radical A ie an alltylene radicalpf from two tofour carbon atom, x has an average value from I to $0, and y is aninteger from 2 to 4.

10. A polymer according to claim 9 wherein A of the formula ispropylene.

ll. A polymer according to claim 10 wherein the curing 'agent it apolyoxypropylene polyamine having a molecular weight from about ISO toabout 3,000.

12. A polymer according to claim ll wherein .r in the ipolyoxypropylenepolyamine formula has an average value of 6 and y is 2.

13. A polymer according to claim 11 wherein x in the poiyoxypropylenepolyamine formula in 3 and y is 2.

14. A polymer according to claim 11 wherein a in the .polyamine formulahas an 21 value of i5 and y il 2. 1 1'5. A polymer according to claim 11wherein x in the polyoxypropylene polyamine formula haa an average valueof 30 and y is 2.

16. A polymer according to claim It wherein a in the polyoxypropylenepoiyamine formula has an average value of i5 and y is 3.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,607,792 Dated September 21, 1971 George Phillip Speranza and HaroldGeorge Waddill Assignors to Jefferson Chemical Company, Inc. Houston,Texas, a corporation of Delaware It is certified that errors appear inthe aboveidentified patent and that Letters Patent are hereby correctedas shown below:

On the first page, under References Cited, "Bvemmer" should read BremmerColumn 1, line 44, after "a" and before "1, 2-propylene" "l, 2" shouldbe omitted; column 1, line 49, the following sentence has been omitted:The invention includes the vulcanizates obtained by using thevulcanizing agents, supra, to cure the halogen-containing polymersColumn 2, line 13, "antidegrandants" should read antidegradants Column4, line 5, "aliphatic radical" should read aliphatic hydrocarbon radicalcolumn 4, lines 19 and 20 should read: "polyoxypropylene polyamineformula has an average value of 15 and y is 2.

Signed and sealed this 2nd day of May i 972.

(SEAL) Attest:

EDWARD I-*I.FLETCHER,JR. ROBERT GOTTSGHALK Attesting OfficerCommissioner of Patents

2. A method for vulcanizing a chlorine-containing polymer according toclaim 1 wherein A of the formula is propylene.
 3. A method forvulcanizing a polymer according to claim 2 wherein the curing agent is apolyoxypropylene polyamine having a molecular weight from about 150 toabout 3,000.
 4. A method for vulcanizing a polymer according to claim 3wherein x in the polyoxypropylene polyamine formula has an average valueof 6 and y is
 2. 5. A method for vulcanizing a polymer according toclaim 3 wherein x in the polyoxypropylene polyamine formula has anaverage value of 3 and y is
 2. 6. A method for vulcanizing a polymeraccording to claim 3 wherein x in the polyoxypropylene polyamine formulahas an average value of 15 and y is
 2. 7. A method for vulcanizing apolymer according to claim 3 wherein x in the polyoxypropylene polyamineformula has an average value of 30 and y is
 2. 8. A method forvulcanizing a polymer according to claim 3 wherein x in thepolyoxypropylene polyamine formula has an average value of 15 and y is3.
 9. A homopolymer of epichlorohydrin or copolymer of epichlorohydrinand ethylene oxide vulcanized with a curing agent of the formulaR((OA)xNH2)y where R is an aliphatic radical, A is an alkylene radicalof from two to four carbon atoms, x has an average value from 1 to 50,and y is an integer from 2 to
 4. 10. A polymer according to claim 9wherein A of the formula is propylene.
 11. A polymer according to claim10 wherein the curing agent is a polyoxypropylene polyamine having amolecular weight from about 150 to about 3,000.
 12. A polymer accordingto claim 11 wherein x in the polyoxypropylene polyamine formula has anaverage value of 6 and y is
 2. 13. A polymer according to claim 11wherein x in the polyoxypropylene polyamine formula is 3 and y is
 2. 14.A polymer according to claim 11 wherein x in the polyoxypropyleneaverage value of the polyoxypropylene polyamine formula has an 21 valueof 15 and y is
 2. 15. A polymer according to claim 11 wherein x in thepolyoxypropylene polyamine formula has an average value of 30 and y is2.
 16. A polymer according to claim 11 wherein x in the polyoxypropylenepolyamine formula has an average value of 15 and y is 3.